Asymptomatic MES detected by transcranial doppler have been reported in patient with ischemic stroke. It has been previously demonstrated that MES predict stroke recurrence and that the frequency of MES depends on stroke etiology. However, the pattern of MES has never been correlated to stroke etiology. Transcranial-holter is a novel ambulatory system which allows prolonged recording (up to 4 hours) leading to an increased detection of MES.